Excel Tables have been around for a decade now (they are introduced in Excel 2007), and yet, very few people use them. They are versatile, easy and elegant. At Chandoo.org, we celebrate Tables all the time. If you have never used them, start with below tuts.
- Introduction to Excel tables
- How to use structured referencing
- Tables and Relationships in Excel
- Using lookups and other formulas with Excel tables
- Simple way to get absolute references in Tables
- Customizing table styles for awesome usability
While tables are super helpful, they do come with some limitations. Today let’s examine one such unique problem and learn about an elegant solution.
Table Relative Reference Problem
Imagine you are the machine supervisor at Mighty Machine City Inc. Although your machines are mighty, sometimes they do fail. To keep track of which machines are under repair, you maintain a repair log in Excel. Since you heard Tables are mighty, you thought,
‘Gee whiz, I might as well use tables to maintain the repair log. Chandoo says tables are sweet’
So, your Repair log looks like this:
After a few days of tracking the repairs, you wanted to know if same machines are failing successively. For example, in above picture, you notice that MACH-0038 failed twice in a row starting with 11th of March. Same goes for few other rows.
You are the kind of person who frowns upon manually highlighting yellow color in cells to flag such successive failures. So you want to write a formula.
So you add a new column called Same? and want to fill it up with a simple relative reference formula to check with Machine in row 1 matches machine in row 2.
Here is the formula you used:
=[@[Machine ID]] = B6
Note: Your table starts with Row 5.
Excel automatically filled down the formula for all rows of the table, because tables are awesome like that.
You whistled your way to home that night.
Next day morning, as usual Homer messed up something and you had a new repair to log. So you went to the bottom of fail table and inserted a new row to add the failure details.
And you notice something unusual.
The formula for Same? column is WRONG!!!
As soon as you inserted a new row, Excel adjusted last row’s formula to something silly.
- Before: Let’s say the last row formula reads =[@[Machine ID]]=B20
- After: The last but one row (as you now have an empty row)’s formula reads =[@[Machine ID]]=B21
Now that is clearly wrong!
What is going on here?
Your relative referencing worked ok, until the last row. At this stage, Excel understood the formula as Current row value = value in first cell below table
The part in green is what caused trouble. As soon as you add a new row to your table, fist cell below table is moved down. So Excel adjusted that reference alone.
How to fix this problem?
The usual method to fix this:
- Insert as many rows as you need and complete entering / pasting all data.
- Select the formula in very first cell.
- Fill it down all the way (you can double click on the bottom right corner of the cell)
But that is soooo not awesome.
You are right. This method is manual and error prone. It is the opposite of awesome.
Problems when you delete too: In fact, if you ever delete a row from your table, the formulas further down would show #REF! errors. So this method is not very effective in real life.
An elegant way to get relative references in tables
Instead of using cell address based references, like B6, if you use pure structured references, then Excel will automatically adjust them as your table grows or shrinks.
But how?
Simple, we can use OFFSET function along with @ references.
To get next machine ID, you can use
=OFFSET([@[Machine ID]],1,0)
So, to check if same machine failed twice in a row, use
=[@[Machine ID]]=OFFSET([@[Machine ID]],1,0)
As this uses no cell references, whenever you add / change / remove table rows, Excel automatically scales the formula.
But I heard OFFSET is volatile / dangerous / RDX / %#$&@#?
Unless your table has a 200k+ rows or you plan to set up 100s of columns like this, don’t bother. for small, day to day tables, there is no change in performance. If you really hate OFFSET, try talking about it during your next therapy session. Jokes aside, you can also use a longer INDEX based formula to get similar result, but that is semi-volatile too.
Here is one such INDEX based formula.
=INDEX([@[Machine ID]]:INDEX([Machine ID],COUNTA([Machine ID])), 2)
It sure is a mouthful. You can shorten it by using a named formula for INDEX([Machine ID],COUNTA([Machine ID])) portion or the whole thing. Again, I wouldn’t recommend the INDEX based approach over OFFSET for smaller data sets. For larger datasets, see if you can fix the problem at source (for example, modifying your SQL to get offset values in a separate column) or using Power Query to mash the data (more on this in a next post).
So there you go, an elegant and simple way to deal with the relative reference problem in tables.
Bonus tip: generating running numbers in tables
You can use this approach to generate running numbers (1,2,3…) in a table column that grow / change / shrink based on your table. This can be very useful in many scenarios.
To get running numbers in a table column, just use:
=ROWS(fail[[#Headers],[Machine ID]]:[@[Machine ID]])-1
The pattern that you can use in any table goes like this:
=ROWS(Table_Name[[#Headers],[Col 1]]:[@[Col 1]])-1
Bonus Bonus tip: If you have running numbers in a column …
You can then change the OFFSET based relative ref to INDEX like below.
=INDEX([Machine ID],[@Running]+1)
This method is 100% non-volatile, but does return #REF! error for the last row. So use it with IFERROR when nesting in other formulas.
Download Example Workbook
Click here to download an example workbook showcasing all these techniques. Use the extra data to paste and test various methods.
How do you write relative refs in tables?
The handful times when I had to use relative refs in a table, I resorted to cell refs (like B6 above). But this created too much headache further down. So I switched to OFFSET / INDEX approaches.
What about you? How do you write relative references in tables? Please share your stories & struggles in the comments section.
Related Reading (no pun)…
If you are relatively free and want some relaxed reading then check out below related reference links.
- An intro to Excel relative references, structured references
- INDEX formula, OFFSET formula, ROWS formula
Happy learning.
28 Responses to “Team To Do Lists – Project Tracking Tools using Excel [Part 2 of 6]”
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Part 3: Preparing a project time line [upcoming] Part 4: Time sheets and Resource management [...]
the templates are great (I bought the combo).
What I'm missing is a way to have the project gantt chart and reporting with the data per resource, in such a way that I can also show the occupation per resource on an extended gantt chart.
So with hours entered per person per project or sub-activity, to show a gantt chart of how many hours/days a person spent on which project (or plans to spend).
[...] from: Team To Do Lists - Project Tracking Tools using Excel [Part 2 of 6] 25 Jun 09 | [...]
Hi Chandoo,
Funny I have a post on the value of MS project lined up which I will post when the current monster project I'm working on finishes and I get some free time!
I'm not sure this would help with any of the projects I've worked on, closing down a to do list seems like more effort than it's worth, but it might be useful for some things. I guessing it doesn't, but does the time stamp not update when you recalculate the work book?
keep up the good work!
Ross
@Ross.. Thanks for sharing your ideas... I think to do lists are a great way to keep up with project activities and ensure accountability from individual team members, when they are implemented right.
"I guessing it doesn’t, but does the time stamp not update when you recalculate the work book?"
Your guess is right. When you change the calculation mode to "iterative", excel takes care of the nittygritties and retains older values in circular references in formulas.
[...] Project Management in Excel [New Series] - Gantt Charts | To Do Lists [...]
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Project Status Reporting - Create a Timeline to display milestones Part 4: Time sheets and Resource [...]
Hi Chandoo,
The template give me lot of convenience to monitor the thing to do. It simple. Thank You
[...] & tracking a project plan using Gantt Charts Team To Do Lists - Project Tracking Tools Project Status Reporting - Create a Timeline to display milestones Part 4: Time sheets and Resource [...]
[...] make sure you have read the first 4 parts of the series - Making gantt charts [project planning], team todo lists [project tracking], project time lines chart [reporting] and Timesheets and Resource Management using Excel. Also [...]
Chandoo,
I really do not see any befit to this function in Excel unless it was somehow tied into some other chart. That is say a scheduled activities % complete is based on the to-do list.
The only way this chart would be useful is if no one was assigned none dependent task that could be done by anyone. The cases were both of these conditions are true are so few and far between it really makes this chart worthless.
@Brian... Once you have a todo list up and running, it is easy to get metrics out of it. I didnt propose it as it might look a bit too micro-management-ish.
I am able to understand what you meant by "The only way this chart would be useful is if no one was assigned none dependent task that could be done by anyone. The cases were both of these conditions are true are so few and far between it really makes this chart worthless."
Can you explain?
"Chandoo"
What I mean is this. Lets say you have 10 task which are part of one activity/WBS that is in your schedule. One there are very few cases were many people would be assigned to complete this one scheduled activity with no direction being given who should what of the 10 task. It is poor management, and the task 90% of the time would not get done in a timely manner if say 4 people were responsible. Secondly, you are assuming all 10 task are independent of each other. You might need to do task 1 thru 3 before you can do task 4, and to do task 7 you might need to do 4 and 6. Thirdly, the time it would take to compile and then fill out the to-do-list even in limited applications is really not worth it.
I just see almost no applications why a team would need to inform others separate from the schedule that they have completed a task on a to-do list unless anyone of the 4 people could of completed that task.
My point is, there might be a few very limited applications for this type of list but this list would be worthless as a Project Management tool in every other case.
However, change this from a to-do-list to a document change log and it is perfect. Instead of to-do it is the documents name or summary of what changed in the document. The person is who edited the document, and the time stamp is when they checked it in. But I do not know why you would use excel when there is free software you can use commercially that is 10 times better that does document management.
I think using excel to do Project Management over a real Project Management application is a bad idea. Unless you are running a very small, simple project, the time and effort is a lot more to use excel compared to the cost of the Project Management software.
This comes back to my point, I love your site, however, just because you can do something in excel does not mean you should do it. To often the time it takes to use excel is wasted 10 times over from the cost of doing it in an application designed to for the specific application.
@Brian: The todo list mentioned here is meant to keep track of all the tasks for which detailed planning is not necessary but some sort of tracking is needed. These are not be confused with project activities (a la gantt chart).
I like your suggestion about using this as a document tracker. Pretty cool use.
Coming to your point about excel as a real project management tool, well, I have my views, but in a serious project environment, it would surely payoff to have a dedicated project management application.
[...] & tracking a project plan using Gantt Charts Team To Do Lists – Project Tracking Tools Project Status Reporting – Create a Timeline to display milestones Time sheets and Resource [...]
Chandoo,
Wonder how the timestamp column will maintain its previous data. Both Today() and Now() functions will update as and when the next timestamp happens.
[...] Preparing & tracking a project plan using Gantt Charts Part2: Team To Do Lists – Project Tracking Tools Part3: Project Status Reporting – Create a Timeline to display milestones Part4: Time sheets and [...]
I've combined this with the issue tracker since I like the automatic date stamp, but one thing I'm noticing is that I can't replicate the chart that goes along with the issue tracker because the cells that are referenced have the formula that inserts the time stamp instead of a the actual date value. All the dates of the last 30 days display 0 when they should have a value.
Is there a way around this?
I have edited the chart so that my team members can update the percentage completion of the assigned tasks. When the cell is updated, i would like the time stamp to update. How would I manipulate the formula to update whenever the drop-down list is changed?
[...] … ??? To Do List [...]
Excel is great however sometimes you need to get a better idea of what tasks each person on your team is working on at any given time. We've developed a web app that can do just that! Each person has a list of tasks, listed in the order they have to complete them.
HII,
I want to expand the database through excel where i am working on 11 cities as of now and i want to expand it upto 50 cities and hence forth the data related to it will also expand so i want to make it precise where i can get updates also that this work is required to be done at that particular day or date
Thanks for making all of this information available for free. I am currently using excel to track everything for the first time. I later plan to output our information here with a more visual presentation. Wish me luck!
Can some one point me out to some additional direction on the "Who Finished it?" column? Something more 'basic' for a newbie excel guy? lol I got everything else working on this tutorial but that column. I can't seem to recreate it and I know a lot of it is due to lack of knowledge with VB code. I'd like to recreate this column very much 🙁
Dear Chandoo,
Thanks for the team to do list, kindly let me know how to set the column who " finished it " from another work sheet
Hi Chandoo,
Unable to download it - can you please check the link and confirm.
Great inhisgt! That's the answer we've been looking for.
Hi Team,
I know u all are the best programmers in the world!!! that's I am here to rectify my issues. here is my question please ans me as soon as possible before 8-3-2017 its really urgent.
I have a project named the production tracker.
1) I require the user form which shows the names of the Associates which are linked to the different tracks. when the user is selected the particular track related details and dropdowns should appear.
2) I need to track the associate needs how much of the time to complete the particular task. with start stop and pause and resume timer.
3) It should display the daily count of the production and save the data to the another Excel file.
this production tracker should save all the data no matter how many people logs in into it.
Please help me for this it will be very appreciated.
you can directly email me on my mail ID: tusharkch694@gmail.com